Inclosed externally-operated time switch



Jan. 1925- 1,521,841

R. D. SMITH INCLOSED EXTERNALLY OPERATED TIME SWITCH Original Filed May8, 1918 8 Sheets-Sheet 1 Jan. 1925- 1,521,841

R. D. SMITH INCLOSED EXTERNALLY OPERATED TIME SWITCH Original Filed May8, 1918 8 heetsheet 2 rainy i, 8

Jan. 1925- 1,521,841

R. EL ShAFrH INCLOSED EXTERNALLY OPERATED TIME SWITCH Original Filed Maya, 1918 8 Sheets-Sheet 3 Jan. 1925- 1,521,841

R. D. SMITH INCLOSED EXTERNALLY OPERATED TIME SWITCH Original Filed May8, 1918 8 Sheets-Sheet 4 fi i 7 Z N 11 c 1 a H3 //e Jan. 192Ei 1,521,841R. D. SMITH INCLOSED EXTERNALLY OPERATED TIME SWITCH 8 Sheets-Sheet 5Original Filed May 8, 1918 Jan. 1925. 1,521,841

R. D. SMITH INCLOSED EXTERNALLY OPERATED TIME SWITCH Original Filed May8, 1918 8 Sheets-Sheet 6 ,IIIII,

Jan. 1925- 1,521,841

R. D. SMITH INCLOSED EXTERNALLY OPERATED TIME SWITCH Original Filed May8, 1918 8 Sheets-Sheet '7 R. D. SMITH INCLOSED EXTERNALLY OPERATED TIMESWITCH Original Filed May 8, 1918 8 Sheets-Sheet 8 Patented 6,1925.

UNITED STATES PATENT OFFICE.

RAYMOND D. SMITH, OF YONKERS, NEW YORK, ASSIGNOB, BY MESNE ASSIGNMENTS,

'I'O TREMONT PRODUCTS CORPORATION, OF BOSTON, MASSACHUSETTS, A CORPORA-TION 0F massnonrosnrrs' INCLOSED EXTERNALLY-OIBERA TED TIME SWITCH.

Application filed May 8, 1918, Serial No, 283,850.' Renewed larch 2B,1928.

To all whom it may concern: I

Be it known that rmness D. SMITH, a citizen of the United States,residing at Yonkers, in the county of Westchester and State of New York,have invented new and useful Improvements in InclosedExternally-Operated Time Switches, of which the following is aspecification.

This invention relates in general to inc'losed electric switches thatincorporate actuation occurs; An example of this type of time switch isdisclosed in my co-pending application, Serial No. 207,303, filed Dec.

15, 1917."; My present invention has as its broad object to switch t atis more simple as to mechanism and more convenient for the layman toopcrate" than time switches as heretofore known; and particularly toprovlde an 1mproved form of safety housing with simple pacity.

exterior-control means for o crating the switch and the timer,-the comined switch,

-timer and inclosing structures embodying co-operative' features ofconstruction an function that. enable my improved time switchsatisfactorily to'meet the many and stringent commercial requirementsimposed upon inclosed, hand-operated, electric switches of considerableload-governingca- Such requirements are, in part, for quickcontact-separating movement at each circult-breaking action of theswitch to prevent arcing; and for special provision regarding ease ofoperation by the layman, involving the necessity for prominent andunmistakrovide an improved form of time able indication as to whetherthe closureconcealed switch is on or off, the provision of safetyinterlockin means between the switch and the move le casing covergoverning access thereto for automaticall guarding the operator fromshock throng accidental contact with electrically alive arts, as well asprovision for permanently ocking the closure of the switch, of thefuses, or of both, to prevent tampering therewith by unauthorizedpersons.

My present invention while providing for requirements such as these mayalso be regarded as an improvement of the timeswitch disclosed in myco-pending application referred to above, and thus viewed has for aspecific object to simplify and render more convenient to manipulate thegeneral type of operating mechanism characterizing that form oft1me-switch;one means to this end, inthe present disclosure, being theelimination of a certain hand-actuated, latch-tripping deviceheretofore. employed in operative association with the usual switchcontrol handle and necessitating, before the present improvement, aspecial mode of manipulation for operating the switch.

- Another specific object of my invention is to provide anovel andelfective spring-butler construction for absorbing the hanimer-blow of.the movable, circuit-governing switch member, which member, in thepresent instance, is acted upon by a spring to cause, in an improvedmanner, the advantageous, quick-contact breaking movement thereof, bothwhen said member is o erated directly by hand and when operateautomatically ated member) operates automatically to perform thelatch-tripping function that requires, in the time-switch of my saidcopending application, special manipulation of the said latch-trippingdevice herein eliminated.

The compactness resulting from this and other simplification, enables meconveniently to house the entire switch and timer structure, with orwithout fuses, in a box or casing of substantially regular outline andattractive appearance,such casing being preferably free from cuts, slotsand the like, as are sometimes employed for the protrusion of operatinghandles in inclosed switch construction. This casing, however, hassuitable openings arranged preferably to give separate-access to thetimer enclosure and to the switch enclosure (which latter commonlycontains fuse blocks).- The opening to the timer chamber maybe closed bya permanent cover attached by screws or other suitable means; but theopening to the switch chamber, particularly when fuse blocks are locatedtherein, must be readily accessible.

Concerning the last-mentioned opening, it is a further object of thepresent invention to provide a movable, and preferably a hinged, covertherefor, mutually co-operating with the circuit-governing switch memberbefore mentioned (or some part connected to move in unison therewith) sothat this movable cover is positively locked in a position to preventaccess to the switch or fuse chamber except when the switch is in itsfully off position; and further so that the switch is positively lockedagainst movementaway from its said fully off position except when saidcover is in its said position for preventing access to the switch orfuse chamben.

Also contributing co-operatively to the stated broad object of theinvention,

mfiy improvement aims to provide an e ect ive means of prominent andunmistakable indication, conspicuous to the opera tors view, forinforming him at all times whether the concealed switch is on or off.Such means of indication are particularly necessary in the specificembodiment of my invention herein disclosed, \for in such embodiment, aswill later appear, the exterior switch control handle does notnecessarily hold a fixed position relative to the inclosed, movableswitch member which it actuates, and, therefore, is incapable of servingas a true indicator of the position of the switch.

In a further developed form, I herein show how this means of indicationmay advantageously be extended to embrace a system of individuallyregistering signs; wherein means are provided not only for informing theoperator as to the true position of the switch, but in a separate casingwindow there is caused successively to appear as a result of eachoperative movement of the circuit-governing switch member alone, of theexterior control handle alone, or of both these arts in unison, adifferently worded sign 0 early directing the operator how next tomanipulate the control agencies (either of the switch or of the timer)for further operating the time switch.

As will be seen from the following detailed description of the specificembodiment of my invention illustrated in the principal figures of thedrawings, all of the improved provisions constituting main features ofthe present invention as outlined above are structurally co-related andco-operative in the production of a common result, namely the provisionof a simplified, inclosed timeswitch, designed for direct, exteriorhandoperation of the switch (as in the case of an ordinary,non-automatic, inclosed knifeswitch), which at once is economical toproduce, well adapted to commercial requirements and particularlyconvenient and suitable for non-experts to use under practical serviceconditions. In addition to the main features of the invention abovereferred to, the hereinafter following description Wlll disclose othernovel and advantageous details, that contribute co-operatively to thebroad object of the invention first stated.

Illustrative embodiment, demonstrating how the principles of myinvention may be applied, and their advantages derived in practice,appear in the accompanying drawings that form a part of thisspecification wherein:

Fig. 1 is a front view of an improved switch and timer structure thatembodies the co-operative features of my invention and shows the switchas tensioned for automatic action under control ofthe timer, the frontcover for the timer chamber being partially broken away to show theinterior parts, and the hinged hood that incloses the switch therebelowpartially appearing in open position and sectioned on the plane 11 inFig. 8, together with certain safety locking parts, cooperatingtherewith. The

shaft) is a false position relative to the interior switch-operatingmechanism as the latter is positioned in Fig. 1.

- Fig. 2 is a complete sectional view taken mainly on the verticallycontinuous planes 2-22, etc., in Fig. 1,but with certain of the timeroperating parts, locally and centrally sectioned better to show theirconstruction, the switch-covering hood here appearing as swung up to itsclosed position.

Fig. 3 is a fragmentary front view showing the upper front cover for thetimer chamber, and certain indicating mechanism partly carried thereby.

Fig. 4 is a view looking in the direction of the arrows from the planein Fig. 2, showing certain details partially concealed in Fig. 1.

Fig. 5 is a sectional view taken on the ing the construction and.relation of certain detent parts through which automatic movement of theswitch is controlled by the timer.

Fig. 6 is a view in right elevation showing the lower part of myimproved time switch with the switch control arm that is exteriorof theswitch chamber positionedcorrespondingly to the interior mechanism asthe latter appears in Fig. 2.

Fig. 7 is a view in left elevation of the lower portion of my improvedtime switch showing the automatically operative parts for effectingsafety interlockingaction between the switch and its covering hood,allof these parts here appearing in their true relation to the interior 1switch-operating mechanism as the latter is positioned in Figs. 1,2 and7, and the said hood being closed, but partially cut away, together withthe casing box, to show certain of the interior parts.

Fig. 8 shows the position assumed hy the parts in Fig. 7 when the switchisin its off position and the switch covering hood is opened.

Fig. 9 is a partial sectional View looking downwardly fI'OIII'thBhorizontally continuous planes 99-9 in Fig. 1, showingthe sameswitch-and-hood, interlocking parts in plan view, together with thesheet metal brackets that support the switch operating inechanism,allmovable parts occupying the same position as in Fig. 7. I

Fig. 10 shows a further developed modification of the type of indicatingmecha-' uism appearing in Fig; 3, together with certain switch-operatingparts as modified to co-operate therewith.

Fig. '11 is a sectional view taken on the vertical planes 1111 in Fig.10. As certain sheet metal sign carriers appearing in this figure are,in actual dimension, very thin and ride substantially in surfacecontact, one behind another, they have been indicated for clearness inthisfigure merely by sin is lines.

*igs. 12, 13, 14, and 15, however, which are fragmentary sections takenres ectively on planes indicated by correspon ing numerals in Fig. 10,by exaggerating the dimensions ofthickness and spacing of these signcarriers, clearly show the co-planar relation of certain ears formed tooverlap at different points on certain of the carriers for co-operatingin the movement of others of the carriers.

Fig. 16 is aview looking at the right of the switch-operating parts ofFig. ;-these parts, in Fig. 16, being shown on the sheet of drawings aspositioned in true operative relation to the indicating parts thatappear in Fig. 11, when the switch is in its oif position.

Fig. 17 shows the indicator parts of Fig.

10 as positioned when the switch is normally established in its onposition.

Fig. 18 is a view looking at'the right of F i 17.

' Fig. 19 shows a change in sign-carrier posafety construction throughwhich the same principles of interlocking action characterizing the camsof Fig. 7 may be preserved when these camsare spaced further apart (asto acommodate the lengthening of the casing indicated in Figs. 20 and21). In Fig. 22, the switch covering hood is permanently locked closedand the switch is in off position but entirely free to be operated.

Fig. 23 is a View taken in'section on the vertically continuous planes23, 23, etc., in Fig. 22.

Fig. 24 shows the parts of Fig. 22 as they are positioned when theswitch is permanently locked in its off position and when the casing isopen but entirely free for,-=" swinging movement to open or close.

Fig. 25 shows how the parts in Figs. 22 and 24 may be availed of to lockthe switch in its off position and at the same time to lock theswitch-covering hood in its closed poslition,permanentlyand by a singlepadloc Fig. 26 is a perspective view of the complete switch-operatingand timer mechanism with the cover parts removed and with the anel finsomit-ted so as to better show details of the mechanical structure.

, F i 27 is a detached View in perspective showing the construction of adetent part.

Fig. 28 is a perspective view of the sign carrier mechanism and certainparts of the switch co-operating therewith.

Fig. 29 is a side view similar .to Fig. 2 showing an embodiment of theaddition of certain spring and detent parts to make the switch perform adouble automatic action at respectively different times under thecontrol of the timer.

Fig. 30 is a front "iew of the timer and detent parts shown in Fig. 29and is taken on the vertical plane 30-30 in that figure.

The same reference numeral, when appearing in more than one of the abovedescribed figures, identifies different viewsof the same clement.

Z710 general structure.

These details of construction that will first be described areillustrated princi ally in Figures to 9, inclusive, of the raw- 'ings.In these figures, the main. parts of In complete switch and timerstructure isregarding, for the present, the housing in whlch they areinclosed) are shown as connected by, and mounted upon, a common supportplate 10 that extends nearly throughout the length and breadth of thecomplete structure at the back thereof. On the upper portion of thisplate is rigidly mounted (in' a manner to be readily removable), byscrews 11 andspacing washers 12, the rear frame plate 13 of a simplebalance-wheel, escapement movement that comprises part of the time laterto be more fully described, and that compositely is designated by thenumeral 14; while to the lower portion of this support plate, is secureda switch panel 16 referably moulded from insulating materia, and, formedwith two forwardly protruding, parallelly disposed, fan-shaped fins 17,that are shownas braced for strength by laterally sloping ribs, 18,

18, etc.

I The switch.

On the switch panel 16-are mounted hinge clips 19, contact clips 21 andcorresponding binding post screws 22 for lead wires 23, the electriccircuit through which is to be made and broken by swinging movement oftwo conductive blades 24, 24,of ordinary knife-switchconstructiom-thcsaid blades being bridged at their tops, as usual, by aconnecting bar 26 of insulating material which is thus carried in aposition to span the channel space between the panel fins 17 17. J

Within this channel spice andefiectively separated by. the panel s 17,17 from all possible interference with, or by, the electricallyaliveparts, is located a. 'rieilgged of switch actuating mechanismcompos few and simple punched metal parts and having operativeconnection as hereinafter to be described with the switch connecting bar26 of theswitch blades.

The frame-work.

and one arm 28 of each bracket ying re-' spectively adjacent to theextreme side edges of said panel while the other two bracket arms 29, 29protrude adjacently through a common central cut-away in the bottomortion of the anel and in the support late 10. At their place ofattachment to the hack of the panel, these brackets, as best shown inFigs. 2 and 9, are rigidly and independently riveted or screwed to thesupport plate 10, which latter overlaps the bracket 27 at the rearsurface of the switch panel,this arrangement providing a cheaplyproduced, but a rugged support-frame structure that entirely relievesthe relatively frail, moulded, switch panel 16 of all mechanical strain.

The actuating mechanism.

As best shown in Figs. 1, 4 and 9, the

two centrally adjacent arms 29, 29 of brackets 27 are parallellydisposed and fall within the channel space between panel fins J17,-there being a small space between said arms to accommodate a switchactuator lever 31 mounted to swing on the bracket-carried pivot pin 32..This actuator lever, as shown, is blanked from fiat sheet metal withoutbends, but as Fig. 2 shows, is cut to such shape that its upper portionis parallelly dis osed in offset relation to its pivoted en'portion,this shape forming two obtuse angle, elbow portions within thelength of the lever. On both sides of that elbow portion of lever 31which is nearest the pivot pin 32, said lever carries a fixed pivot stud33, on which, respectively, swing two arms of a bent-metal bufierstructure 34 formed to straddle the actuator lever and having an uppercompoundly bent portion 36 interposed between ihe actuator lever and theswitch blade connecting bar 26.

For co-operating with the actuator lever '31 and its carrier bufi'erstructure 34, in a manner later to be described, the connecting bar 26carries a bent metal bracket fitting 37 composed, of a mounting okeportion capping the connecting bar 'an see cured thereto by the screw 38'as shown in Fig. 5; and. also having a rearwardly and downwardlyextending portion 39 that provides a rigid and convenient anchorage ointfor one end'of the main, coiled, switc -operating spring 41, the otherend ofwhich latter is hooked through a hole at 42 in the actuator lever31.

The buffer structure 34, as a whole, may

swing about pivot 33 relative to lever 31' between its position shown inFig. 2 and its position shown in Fig. 8, its swing in the formerposition being limited by the with-a rear, upright edge of said lever.,

The coiled hub spring 46, best shown in Figs. 2 and 4, acts on thebuffer structure to urge the latter to its position as shown in Fig. 2.Obviously the powerful switch -actuating spring 41 tends to hold theswitch blade and the actuator lever 31 with its carried bufler structure34 in their relative angular position as shown in Fig. 8; and

since from Figs. 1 and 2, it is clear that the illustration, showing abail crank 47 pivoted at 48, 48 at the sides of the support bracket sidearms, 28, 28.and concentrically with the pivots of the switch blades 24and. of the actuator'lever 31. This bail. member, asshown, is twisted ata central point 49 in its spanning portion, so as to engage with a slotcut in the extreme upper end of the actuator lever,this constructionpermitting of ready disassemblage of parts and also allowing. of slight,radial movement to compensate' for lack of absolute concentricitybetween the bail crank and actuator lever pivots. As will later appear,the bail crank 47 is ordinarily inclosed within a casing, and,accordingly, I have provided a radial control arm 51 for operating thesame, disposed to limit to swing outside of the casing and carrying thecrank handle 52 at its end. In Fig. 6,

two casing mounted check studs 53,53 are shown as co-operatlng with arearwardly extending portion 54 of the arm 51 directly thus to renderimpossible any strain on me interior. mechanism through abuse of theswitch control arm.

= .Method of manually operating switch.

So'much'of the actuating mechanism as I have already described, initself, constitutes an improved construction in quick-break,

"hand-operated knife switches because of its tension of the clips 21against the blades ofiers appreciable frictional resistance to theirwithdrawal, so that upon swinging the control arm 51 forwardly, thisfrictional resistance ordinarily is not overcome, until a preciableseparation has occurred between t e actuator lever 31 and the connectingbar 26. Such separation obviously increases the tension in theconnecting spring 41, tending to pull the blades out o engagement withthe clips, so that at some point in the forward and downward swing ofthe actuator lever 31 this tension will have become strong enough toovercome the retaining the actuator lever 31.

e latters swin in movement friction and. cause the blades quickly tosnap away from the clips 21, again to assume their normal abuttingposition relative to When this action occurs the blow of impact betweenthe bufi'er structure 34 and the connecting bar bracket 37 is to a largeextent absorbed by the spring-opposed yielding of the buffer structure34 to its retracted position shown in F ig. 8.. It should beparticularly noted, that laws of inertia and of static friction makenecessary a-greater accumulation of tension in spring 41 to overcome thedead friction of clips 21 when the arm 51 is moved very slowly than whenmoved very quickly,

bringing about the advantageous result that Timer controlled dctentparts.

The foregoing description has disregarded the presence of certain detentand catch parts that are involved in the timer-controlled, automaticoperation of my improved form of switch actuating mechanism and thatwill now be described. In Figs. 1, 2 and 4 the buffer structure 34isshown as provided with two similar, downwardly extending portions atopposite sides of the ad jacent bracket arms, 29, 29 and each formed asa catch 56 which is operatively positioned to engage with a double latchmember 57 pivoted at 58 also on both sides of said bracket arms andurged by a spring 59 to its position shown in Fig. 2, where a connectingportion 61 of the double latch member acts as a stop against the frontedges of the sup.- port bracket arms. The dot-dash lines in Fig. 2 showhow in the before-mentioned, retracted position of bufier structure,the" catch 56 is normally held out of position to engage with latch 57;and from the foregolng, it will have become apparent that this catch isalways so inoperatively held while the switch blades 24 and actuatorlever 31 swing in unison relatively positioned, as in Fig. 8. Accordinglno interlocking of catch 56 and latch 5 can occur during ordinary,direct, hand-actuation of the switch such as heretofore has beendescribed.

Other detent means, also, are provided for arresting the switch bladesin their cirspreading the metal to form a hollow in the dogs pivotedportion therebelow, on each side of which hollow portion two stop-feet66 of the dog extend downwardly to en gage with a shelf 67 that isformed in the bent metal connecting bar fitting 37-for lim'ting theupward movement of the dogs nose portion. Figs. 1 and 5 show a detentlever 68 free to swing on a pivot pin 69 mounted in bracket ears -71struck forwardly from the support plate 10, the forwardly extending armsof this lever-carryin" be tween'their ends, a spherically shaped, detentblock 72 having a central recess 73 cut obliquely therein as shown inFig. 5. detent block is so positioned throu habutment of the lever 68againsta stop 4, as to fall directly in front of, and in position toenga e with, the nose of dog 63 when the switc blades-are nearly seatedin their contact clips. Bearin on the upper, sphericalsurface of thebloc 72 is a presser f0ot7 6, carried bythe feeler lever 77 andvertically adjustableon 'the latter by means of the screws 78, 78. Thefeeler lever 77 is bent at its mounted portion so as to have hearing attwo oints on a pivot bolt. 79 which near its head passes throu h, and issupported by, an overhanging bracl ret formation 81 struck out from thesupport plate 10, and also screws into the support plate 10. A lightcoiled spring 82 assists gravit in normally urging the swingin detentblock 72 and .presser foot 76, to t eir lower positions so that theformer may be engaged by the nose of the latch dog 63 as clearly shownin Fig. 5. The nature of this engagement however is such, as will beapparent from inspection of Fig. 5, that the forward thrust of dog 63 onthe detent block 72 acts in such angular relation relativeto the ivotpin 69 of lever 68 as to urge the said lock and lever upwardly about thepivot pin 69 to permit escapement of the dog. The proportional magnitudeof the force component tending thus to thrust the block upwardlyrelative to the total pull exerted by spring on the connecting bardepends on the an le of engagement between the block 72 anll the dog 63.It will be noted that the reactive thrust on the dog is in suchdirection relative to the latters pivot 62 as to be ositively opposed bythe abutment of the ogs foot portion 66 against the bracket fitting 37.Downward yielding of the dogs nose portion, however, may always act toermit the dog to pass the detent block (whet er or not the lattercanyield upwardly) in the op o-.

site relative dlrection of travel. I pre erably arrange the angularrelation of engage-.

ment between do 63 and block 72 so that only a very sm pro rtion of thetotal force of spring 41, ten ing to pull the dog forwardly past theblock, is transferred into a component effective to urge the'block up-This wardly, and, accordingly, by far the greater part of this force isborne as a direct pull upon the' pivot pin 69. Even this small componentof force however is, in effect, still further diminished throughmultipli cation of leverage so that ultimately a very slight pressureapplied downwardly at the upper, free end 83 of feeler lever 77 isogerative' positively to block the upward yiel ing ten blades are putunder the relatively heavy tension of spring 41 to cause theircircuitbreaking action.

T he timing mechanism.

Identically as in the structure of my copending application,hereinbefore referred to, it is the function ofthe simple timermechanism employed to block and at a predetermined time to release theend 83 of feeler lever 77' to prevent or permit the above describedyielding movement thereof at each forward escapement of dog 63 fromdetent block 7 2 as is necessary to permit circuit-breaking action ofthe switch. This timer mechanism is fully described in detail in my said.co-pending application, and therefore it will suffice here to statethat the immediately operative element thereof is a rotatable cam 84mounted on a squared portion 85 of the main, timer-spindle, which latterhas hearings in the frame of the esency of the detent parts when the,

capement movement 14 and is constantly urged to rotate clockwise (asviewed in Fig. 1) by the band spring 86, to a stop-limited position asdetermined by en agement of the cam carried arm 87 with a rame mountedstud 88. All spring-caused, clockwise rotation of this cam and spindle,however, is

retarded by the balance-wheel escapement 1 not .movement above mentionedthat is fully control-hand 89 in either direction to any desiredrotative position,the degree of en ergization of band spring 86 beingalways proportional to the amount of counterclockwise,rotativedisplacement of the timer control hand 89 from its zero position(indicated by dot-dash lines in Fi 1). In this figure, however, theccntro hand 89 is shown (in full lines) as set at the graduation 10 onan associated, casing-mounted dial 91, that is appropriately marked toindicate the time consumed in return of the pointer handle to its zeroposition from its different possible time settin s. Also in Fig. 1, anotch 92 in'cam 84 is's own as correspondingly displaced from a normalsition indicated 'in dot-dash lines, in w ich latter position(corresponding to the zero position of the timer control hand.)it'registers with the end 83 of feeler lever 77 so that the latter mayenter this notch for permitting circuit-breaking movement of the switchblades. I

Attention, however, is particularly called to the improved constructionmy present invention provides for mounting and operating the timer cam84. The hollow hub 93 of this cam contains a compression spring 94retained by the spindle terminal nut 96, this spring constantly urgingthe cam rearwardly to an axial position for operative alignment with theend of feeler lever 77. The' novelly formed, one-piece, punchedmetalcontrol hand 89 for the timer, which is retained on a squared terminalof hub 93 by the cap screw 97, is cheap to construct and is convenientto manipulate for turning the cam 84 to its desired operating setting,as well as for pulling the same' axially for- -wardly as a means forinstantly effecting release. of the switch from control of the timer.'Heretofore direct hand release of the switch for circuit-breakingaction, after the timer has been set in o eration, has necessitatedrotatively returning the hand to its zero position,-removal of the camfrom engagement with feeler arm through axialmovement being, in thisconnection, an improved and more 'convenientmethod of etfecting suchrelease. The novel details of my invention just described simplify andrender more convenient to operate analo gous parts as heretoforeconstructed in apparatus of this charactelm M ode of. operation undertimer "cont/"0?.

.VVhen the timer is to be used for controlling automatic,circuit-breaking action of the switch blades (which action, as effecteddirectly by hand manipulation has hereinbcfore been described) the ooration is as follows. -Either before, or a ter, the switch is closed,the timercontrol hand 89 may be turned counter-clockwise away from itsnormally idle zero position to the desired time setting. Upon release,it automatically. begins its-retarded, spring-driven, return to its zeroposition. The band spring 86 has been wound by this'setting operationand the cam 84 rotated so that its notch 92 is removed from position topermit yielding ot' feeler lever 77,-the periphery of said cam nowpositively preventing such yielding, until return of the notch 92 to itsdot-dash position in Fig. 1. The detent block 72 is thus locked in itslower position by the presser foot 76 and in such position will preventassage of latch dog 63 *when oncountere by the nose thereof in openingmovement of the switch blades 24. The actuator lever 31, however, whenswung forwardly, to tension the springatl, becomes automatically lockedin its extreme outward and downward position (as shown in Figs.

1 and 2) through engagement of catch 56 with latch 57, these parts beingeo-operatively formed to pass smoothly into locking engagement. Theswitch is now set for timer-controlled, circuit-breaking action.

Although en'iergency means for manually tripping the latch 57 to freecatch 56 are provided in the bell-crank arm 98 that extends rearwardlyand downwardly through a slot in the bottom of the casing box (as shownin Fig. 2), I will now point out a novel and advantageous feature inautomatic switch action resulting from the improved arrangement of partsthat lhave devised. Upon timer-determined circuit-breakingaction of theswitch blades, the hammer blow of connecting bar 26 against the bufferstructure 34. as before stated, is mostly absorbed by causing the latterto yield to its retracted position indicated by dot-dash lines in Fig.2. It will be obvious, however, that such yielding of the buii'erstructure results automatically in the disengagement of catch 56 fromlatch 57 so that the very locking means which havingbeen maintainingtension in spring 41 tending to cause circuit-breaking switch movementbecome unlocked by, and near the extreme end of, that movement. Thisautomatic action eliminates the necessity fonproviding means manually torelease the catch 56 each time before closing the switch.

Since, however. the tension in spring 41 acts to effect no absolutemovement of the blades (but only their movement relative to the actuatorlever. which itself is pivoted and free for movement except when lockedby the catch 56) it follows that after such automatic unlocking of catch56 as described above, the blades have no more tendency to continue intheir direction of circuit-breaking movement than the actuator lever 31(now also free for movement) has to fly up to meet the connecting bar26.except for such kinetic energy as is possessed by the connecting baras a result of its initial momentum. From inspection of the relation ofparts and consideration of the mechanical conditions involved. it willbe apparent there may arise a distinct tendency of the actuator lever31, and thereby of the switch blades 24, to rebound in the direction oftheir switch-closing. swinging movement unless some means counteractingsuch tendenc is present. Obviously.I might provide a riction seating orthe like that would catch and hold the switch blades in their extremeoff position. But the necessary resistance exerted by such seating, andconstituting its use, would then be encountered at each direct, handcontrolling 'movement of'the switch ,'-an undesirable feature, since aprimary object of the present invention. is to provide a time switchwhose normal operative characteristics are solely those of an ordinary,hand-operated knife switch.

Shock-absorbing buffer 'rrwciuzmlsmt.

I will, therefore, point out in detail how the character of arrangementthat I have devised, without employingatdditional elements for thepurpose, ositively counteracts all tendency of the lades to rebound, andin addition constitutes a shock absorptive contrivance of such merit,that by actual test, although the tension in spring 41 and the blow ofthe circuit-breaking switch parts caused thereby are necessarilyconsiderable, yet the shock of that blow is so effectively dampened,that when the entire structure sits upright, on end (as positioned inFig. 2 and without fastening or support of any kind) no perceptiblemovement of the structure as a whole is caused by the abrupt andpowerful automatic switch action.

Referring to Fig. 2, it is apparent. that tendency of the actuator lever31 to rebound in a direction to close the switch must constitute atendenc of this lever to turn about its pivot 32. e effective magnitudeof such turning tendency, (known to the me chanically skilled asaturning moment) is, in part, determined by the distance from the saidpivot to the point of application of the acting force (in this case thereactive force of impact). 'More accurately, how-. ever, such turningmoment is directly proportional to the perpendicular distance from saidpivot to the line of direction of the effective component of the appliedforce, such effective component, of course, being that part of the totalapplied force which acts in a direction tangential to the arc ofmovement of that point on the actuator to which it is applied. This ismerely saying, that the magnitude of the tendency of the freelyswingable parts to rebound is proportional to the effective leveragepossessed by the force of impact in respect to the pivot of the actuatorlever. The smaller, therefore, such leverage can be made, the smallerwill be the tendency of actuator lever 31 to rebound as a result of thehammer blow of connecting bar 26 against the buffer structure 34. whichblow, after full yielding moment of the buffer structure, must, ofcourse, ultimately .be transmitted to the actuator lever, since thebufier structure is wholly carried thereby. Based upon considerations ofthese simple principles of mechanics, I have devised a shock absorbingarrangement composed of simple pivoted parts whose novel features may beavailed of to advantage in connection with buffer structures in generaland regardless of the particular nature of the apparatus with which theyare used. The novel principles referred to are broadly these: Bypivotal, (or other) .Inovahle mounting of a yieldingly-positioned bufierstructure on a separately and eccentrically pivoted carrier member(required to be free to turn about its pivot), and by providing astationary stop abutment, operativel independent of the said ivotedmember, ut positioned to" be struc by the said. buffer structure forultimately checkln this principle of arrangement and action in bufferconstruction is next described.

It is clearly shown in Fig. 2 that the buffer structure 34 when struckby the connecting bar fitting 37 yields abruptly to its positionindicated by dot-dash llnes. But

here it is to be noted that before the for-v wardly bent portion 44 ofthe upper buffer structure reaches the ed of the actuator lever 31 (aainst which it is designed norm'allv to a ut as shown in Fig. 8), theshoulder portion 99 of the buffer has encountered the top of latch lever57'. It is only for convenience of design in the particular structureconcerned that the latch 57 serves thus as a positive independent stopabutment for the buffer; as any stationary abutment correspondinglypositioned would serve the same 0 erative results. .Obviously the forceof t e impact between buffer structure 34 and the latch 57 (orequiva-,105

transmitted to the pivot 33 of the buffer as a pull almost radially inrespect to the pivot 32 of the actuator lever. words, the force ofimpact, as ultimately transmitted tothe actuator. lever 31. acts in aline of direction passing through the lever pivot 32 and therefore setsup no appreciable turning moment in eitherdirection of swing andtherefore no tendency of the actuator lever 31 to rebound in a directionto close the switch, thus enabling this lever, at the end of theautomatic action, to be left unrestrained and entirely free for furthermovement. The switch blades 24, themselves cannot, of course. reboundbecause they are connected by the heavy spring 41 to the actuator lever.It should further be noted that did the nature of the apparatus sorequire the lever 31 could as well be left free for further-downwardswinging movement and still, through the principle of buffer action Inother above described, serve the double oilice of carrying the bufferand of acting as the ultimate ositive stop therefor when thelatteryields to the blow of impact.

The indicator mechanism.

I will now refer to the casing parts, hereinbefore disregarded, and thendescribe the novel and simple means illustrated in Figs.

,7, 8 and 9 for effecting co-operative,

safety interlocking action between my improved switch and its coveringhood, to prevent accidents to the operator, through thoughtless contactwith a live switch fuses.

As Figs. 1 and 2Mclearly'. show, these casing parts comprise principallya plain, rectan'gular, punched-metal box 101, the upper ortion of whichis covered by a compound also cover comprised of a front plate 102 and apartition plate 103 in the rear thereof and spaced therefrom, whichcover is secured by screws 104 to cars 105 formed at the edges of thebox. Between these spaced cover plates, as a convenient means forregistering on and folf positions of the switch, 1 may mount, as showninFig. 3, a swingin sign carrier 106 pivoted at 107 and normally held inan uppermost position by the spring .108, but depressible againstthetension of this spring to a lower osition wherein the carrier signreading On registers in a window opening 109 in the front plate there byto obscure another, stationary sign read- ,ing Ofi that is permanentlylmprnted on 'nection between the carrier 106 an r the switch, v.1 mayprovide the simple crank 7 wire 111 that is conveniently mounted to'""111," as W511 as the 'entireswitch with its swing in a bracket/112formed by forwardly projecting portions of the partition plate 103. Onearm of the crank wire 111 passes 'rearwardly through a cutaway 113 inthe front plate to engage the carrier 106 while the other and longer armis curved and ex tends downwardly to be actuated (in a man ner clearlyunderstood fromFigs. 2 and 3),

2 1 make contact with the slips 21 in the circuit-closing movement ofthe switch.

' The interlocking safety enclosure.

Inclosin the sign-actuating crank wire operating mechanism, is aforwardly bulging cover hood 114:. This hood is hinged at rearwardlyextending lower portions of its side walls (that overlap the sides ofeasing portion. The cam 118, before mentioned, is

axiallyslidable on the outer squared portion 122 of this shaft but isnormally maintained at an innermost position thereon by the compressionspring 123 retained within a punched metal hub portion 124 of the cam118 by a hub guide nut 126 mounted at an outer threaded extremity of thesquared shaft portion. At its innerend the shaft has riveted to itsother and shorter squared portion the radially extending upright plate127, to which latter is'securely fastened a block 128 of insulatingmaterial, the opposite face of which is grooved to engage, and swingwith, the left switch blade 24, between its hinge clip 19 and contactclip 21. A retaining screw 129 holds the block and blade in positiveengaging relation while permitting relative radial sliding movementtherebetween, if necessary, by means of the elongated slot 131 in block128.

Figs. 7 and 8 clearly show the plate cams eration, while efiected byvery simple means,

provides a desirable form oflsafet construction that guards mosteffective y against shock to the operator through careless contact withlive switch parts by making it impossible for the operator to'haveaccess to the switch except when the latter is in its fully 05 position.The squared shaft 121 and retaining spring construction are provided.-however, to permit convenient removal of the self-restoring cam 118 fromaxial alignment with cam 117 thus to threw the parts out of interlockingrelation when for some designed purpose it is necessary to close theswitch with the casing open.

' In addition to the-automatically acting lock cams 117 and 118,- Figs.7, 8 and 9 show a convenient construction that may be compactlyassociated-therewith for permanently preventing (by a common padlock131) all access to the switch chamber (and in. the form shown, also tothe timer chamber) except by authorized persons. This construcw tioncomprises a hinge bracket 132 mounted on the side of the casing box 101to which bracket ispivoted the swinging lock bar 133, the latter beingprovided with a slot 134 adapted to engage a projecting tongue 136formed on the hood cam. As the bar 133 swings to its locking position,shown 1n Figs. 7 and 8, Wedging action between the left end of slot 134and the left edge of tongue 136 forces and holds the switch cov eringhood tightly closed.

Automatic sign mechanism.

Attention is now directed to Figs. 10 to 18, inclusive, wherein, for thepurpose of causing appropriate operating directions to appear atdifferent times, there is shown an e aboration of the general type ofindicator mechanism of Figs. 2 and 3, comprising a plurality of pivotedsheet metal sign carriers, of which the carrier 106' operates similarlyto, and bears the same On sign, as the carrier 106 in said Fig. 3. Buthere the former carrier is arranged, by its up and down swingingmovement to effect simultaneous up and down swinging movements of asecond sign carrier 137 pivoted idly at 138 to the front plate 102 andnormally positioned .to fall diagonally across the carrier 106 in backthereof as shown in Figs. 10 and 11. Interposed between front carrier106 and rear carrier 137 is a third carrier 139 that swings on the samepivot 138 with rear carrier 137. Reference may be had to the fragmentarysections shown in Figs. 12

to 15, inclusive, for better. understanding the following description ofthe exact construction. In said figures, the three vertically alignedpairs of dot-dash lines by greatly exaggerating dimensions of thickness,represent in side elevation the closely adjacent planes in which thethree sign carriers 106', 137 and 139, respectively, swing. Each ofthese. carriers is stamped from thin sheet stock and is entirely flatexcept for certain overlapping ears formed co-operatiyely therewith, andin a co-planar relation thereto, the other .carriers that is clearlyindicated in the last mentioned figures. The ears 141 and 142, shown assectioned respectively in Figs. 12 and 15, extend rearwardly from thefront carrier 106 and overlap rear carrier 137. without interferencewith intermediate carrier 139, to guide the rear carrier 137 at itspoints of engagement by the front carrier throu h which it is actuated.In the downwar swinging movement, this actuation occurs through camaction of'the right band edge of ear 141, where it is turned backwardly,with the upper convex edge 143 of a spur formetion on rear carrier 137.In upward swinging movement the front carrier 106' swings the idler rearcarrier 187 simultaneously upwardly through eo-operative cam actionbetween the upper edge of ear .142 (where it is turned backwa-rdly) witha lower convex edge 144 of the rear carrier. Figs. 13 and 14 show theonly operating connection of the intermediate carrier 139, thisconnection comprising a curved tongue 146 bent sharply to the rear fromintermediate carrier 139 and immediately upwardly after passing througha correspondingly curved slot 147 in the rear carrier 137. As clearlyshown in Fig. 13, the tongue 146 at its lower portion is normally helddownwardly against the lower edge of the slot 147 b a light wire spring148, which latter at its ree end is guided in a seat formed at the backof the rear barrier by said tongue, this spring being anchored at itsopposite end in a rearwardly turned ear 149 formed from the rear carrier137 as plainly shown in Fig. 14. Normally, the spring 148 acts to holdrear carrier 137 and front carrier 106 in their aligning position shownin F igw 10, but may bow resiliently to permit relative separatingmovement therebetween in one direction of swing, as hereinafter to bedescribed Fig. 10 shows a new element added to the switch-operatinbail-crank 47 that engages the actuator ever 31, this element being arigid wiper tongue 151 secured, for convenience, to the under side ofthe said bail-crank and extending rearwardly therefrom at a pointslightly to the left of its center. This tongue as viewed in Fig. 16,conforms to the curve of a circumferential arc relative to the pivot ofbail-crank 47. Fig. 10 also shows, in addition to the bracket-supported,carrier-operating, crankwire 111 of Figs. 2 and 3, a similar crankwire152 pivotally carried by bracket extensions 153 similarly formed fromthe partition plate 103,one arm of the latter crankwire extendingrearwardly to work under a forwardly projecting lug 154 on theintermediate carrier, and the other curved arm extending generallydownwardly to be en countered by the above described wiper tongue 151. Astop clip 150 is carried by each of crank-wires 111 and 152 to limittheir downward swing. The carriers 137 follows. 7 n

Operation of the sign mechanism.

When looking at the front of the inclosecl time-switch, the operatorsees before him in the two front-plate windows, one of the differentsign combinations appearing either njFig. 10, Fig. 17 or Fig. 19.Assuming that the switch is open, he is confronted .which arrow in theassembled structure points directly to the switch control. arm 51 at theright of the cover hood 114. The latter sign clearly directs him how toclose the switch. It should be noted that the sign Swingarm up as'is thecase with the sign Oil is stationary and carried by the partition plate.When the operating directions are followed and the control arm is swungup to close the switch, the visible signs-are changed to. thoseshown-nsre 'ister'ing in the two windows in Fig. 17. uch change of signsin the left window has been caused by the depression of carrier 106against the tension of spring 108 exactly as in the construction ofFigs. 2 and 3, the stationary Swing arm up sign in the right window atthe same time having also been covered by downward swing of the rearcarrier 13'? as efiected in a manner heretofore described.

against the tension in spring 148 that now tends to swing theintermediate carrier 139 downwardly. Since the wiper tongue 151 engagescrank-wire 152 for holding intermediatecarr'ier'139 up, at substantiallythe same time crank-wirev 111 is encountered by the pin '62 to depressthe front and rear carriers 106 and 137, it follows that in ordinary,direct, hand actuation of the switch operating directions theintermediate carrier 139 and its sign Turn hand back never appears inthe window 155. The operator in the position of parts in Fig. 17, readsOn in the left.

window informing him that the switch is closed, and in the right windowreads the Swing arm down informing him how to manipulate the controlhandle to open the switch. On again closing the switch it will heunderstood that the spring 108 restores all carriers to their upperposition thus clearing the windows in the front plate of all. movablesigns.

The function of the sign worded Turn hand back will now beexplained. Itwill be recalled that there is a possible third condition of theswitch-operating mecha nism in which the switch is tensione'd forautomatic, timer-governed actuation, and in which condition of theoperating mechanism the switch control arm 51 is locked in its lowerextreme position by catch 56 and.

the switch. Itis the function or the Sign -Turn hand back, borne by theintermediate carrier 139, to inform the operator concerning thisdifferent mode of operation the switch is tensioned and under control ofthe timer, the sign Turn hand back is caused to appear in window 155.Fig. 19 shows the switch blades 24 held in their on position by thetimer controlled detent parts,this closed condition of the switchremaining truly registered by the sign On in the left window of thefront plate, but said figure also represents the switch control arm asdepressed and the actuator lever 31 accordingly withdrawn and locked inposi tion for tensioning the switch. Accompanying withdrawal of thetongue 151 on bail-crank 17 has released the crank-wire 152 andpermitted the intermediate carrier 139, with its sign Turn hand back todrop in front of the Swing arm down sign under impulse of the wirespring148. It will be noted that the latter sign also has an arrow butthat this arrow points to the timer control hand 89 thus unmistakablyindicating the control agency of the time-switch to which the signrefers, and plainly informing the operator (who presumably has justturned the timer control hand away from its zero position for puttingthe switch under timer control) that to open the switch he must returnthe timer control hand to @bviously the latter mentioned sign might'asappropriately be worded Pull hand forward It will be appreciated thatthe wordingiot the signs as employed in the indicating mechanismdescribed above is but arbitrary, and is intended merelyto illustrate anovel operative principle applicable to indicating mechanisms ingeneral, the principal and obvious advantages of which resides in thatgreater simplicity and which results from the timely and automaticpresentation ofoperating directions only in such part as is"pertinentfor instructing the operator how to manipulate the control agencies inthe existing operative condition of the apparatus. The oldand customarymethod for presenting operating directions in connection with vapparatus requiring special and unfamiliar methods of manipulation hasbeen to list such direction in their entirety on a name plate or someconstantly exposed part of the structure, thus requiring the unskilledoperator to study and become familiar with all of the operatingdirections before he can correctly and with convenience self-evidentncssmake any use of the apparatus concerned.

It is, believed that the provision of an arrangement designed to presentsuccessively only the pertinent parts of a complete set 1 of operatingdirections is broadlynovel and that its practical advantages over theold -method of listing operating directions in full are self-evident.Modification of the interlocking enclosure.

- 'hinging the switch covering hood 114 is to be preserved, suchlengthening of the casing may require appreciable further separation ofthe pivots for cams 117 and 118, in Figs. 7 and 8. Since in some casesit might be inconvenient to compensate for such increase in pivotspacing by sufficiently extending the peripheral portions of said camsto maintain their direct interlocking engagement, I have shown in Figs.22 to 25, melusive, how I may interpose-idler lock means mounted to oerate between two equivalent cams'117 an 118 that are mounted to turn inunison with the cover hood and the switch blades, respectively, in themanner of cams 117 and 118 above mentioned. Such lock means, however,are preferably arranged in a way to retain the same simple and effectiveprinciples of interlocking action illustrated in Figs. 7 and 8. Asdisclosed herein, such interposed lock means constitute two pivotedidler plates 15 6 and 157, although a single member could for mostpurposes as well be.

substituted therefor. These idler plates lie flat against each other andare retained in contact, frictionally, if desired throu h pressure of a.spring such as 158 under t e head of screw stud 159 mounted on the sideof the casing box 101. The inner plate 156 at its radial extremity hasan outwardly rojecting lug 161 a ainst which an under concave edge of te outerplate 157 abuts. From the nature of their mounting it will beunderstood that these two plates yieldingly maintain any rotativeposition to which they are moved. An oblique edge 162 near the radialextremity of the outer plate is swingable to a position for engagementwith a corresponding oblique edge 163 of the switch blade-connected cam118" and a similar obli no edge 1640f the inner plate adjacent the iug'161 may swin to a position for enagement with an obi ue edge- 165 of thelioodrarried cam .117 The nature of obli uity of the cam edges referredto above is o viously suclt in relation to the ivot point of cams and'tothat of the idler p ates, that either cam is adapted to thrust itsassociated idler late from the path of cam movement on ess said plate isby some means held against turning. Each of Figs. 22, 24

and 25 shows the plates thus positively hold in respectively differentrelative or absolute positions by a lock pin 166 carried on a lever 167hinged at 168 and having for convenience of manipulation a handle knob169. The lock pin 166 is adapted for insertion in either one of a pairof adjacent holes 171 through each of the idler plates and then into aregistering hole 172 in the side of the casing box. Eachpair of the lockpin receiving holes in each idler plate may respectively align, astheyare shown in Figs. 22 and 2 1, or only two of the four holes may alignas shown in Fig. 25, thus enabling the lock pin to secure-the idlerplates in any one of three different combinations of positions Thepadlock 131 is accommodated by a hole in the fixed bracket tongue 173mounted on the casing box 101 in a position to pass through a slot 174.-in the lock carrying lever 167.

Operation of the modified interlocking enclosure.

In describing the operation of the safety and locking constructiondescribed above the lock-pin 166 will be considered as withdrawn, orpositioned, as shown by dot-dash lines in Fig. 23. The idler lates 156or 157 are now free to be shifted in unison at the urgency of either ofcams 117 or 118 but only when the other'of said cams is positioned as inFi 22. In Fig. 22 the switch is supposed to be open and the cover hood114 is shown as closed. Although the inner idler plate 156 is shown inthis figure as lying in the path of movement of the hood, cam 117', itis obvious that movement of thelatter cam in a clockwise direction (asoccasioned by opening of the hood) thrusts said plate from its path andthereby the plate 157 into the ath of the switch connected cam 118'. uchdisplacement ofthe idler plates, however, could not occur if the switchwere in other than its off position, for in such other position, the cam118' would occupy some correspondingly displaced position as indicatedby dot-dash lines in Fig. 22, wherein its peri heral portion positivelyblocks the idler p ate against yieldmg movement. Thus'opening of thehood is positively prevented except when the switch occupies its fulloff position. as in the case of the two directly engaging cams of Figs.7 and 8. On the other hand, the insertion of lock pin 166 in itspadlockretained position as shown in Fig. 22, may itself permanentlylock the hood alone closed. In Fig. 24 a similar condition of automaticlocking operation is shown in respect to the switch cam 118 whichoperation will be selfevident from an inspection of the drawings in viewof the above description. Fig. 25, however, shows how, for locking theidler plates in separated position so that each-

